Is Sierra McCormick a Cousin or Niece to Maureen McCormick?

Sierra McCormick is the niece of Maureen McCormick. Maureen McCormick is best known for her role as Marcia Brady on "The Brady Bunch," while Sierra McCormick is an actress known for her roles in various television shows and films. Their familial connection is through Maureen's sibling, making Sierra her niece rather than a cousin.